(6) A bullet is red from the ground at an angle of 453" above the horizontal. What initial speed must the bullet have in order to hit a point 100 meters high on a tower located 200 meters away? Note: You may use IOm/s2 for gravity acceleration. (7) A ball is thrown at a height of 1.2m above the ground with an initial speed ZOm/s at an angle 60 above the horizontal. Note: Use 10m /s2 for gravity acceleration. (a) Find a vectorvalued function r(t) describing the position of the ball. (b) Find the time at which the ball strikes the ground. Hintzm = 18. (c) Find the horizontal range of the ball. (d) Determine the maximum height of the ball